So Gunderson has signed up for every genetic test he's been able to afford. And he can't wait for the price of getting his entire genetic code — his genome — to drop to about $1,000, as many are predicting is imminent.

"Yeah, if the price does drop — to a thousand bucks for example — I might pay that. That's a good personal price point for me," Gunderson said.

So-called whole genome sequencing is already available for between about $4,000 and $10,000.

"The early adopters that are getting this done now are those who have this incredible curiosity about their genetic makeup, about their potential genetic destiny," said Jay Flatley, who heads Illumina Inc., of San Diego.

Illumina even recently started offering an iPad app that people can use to learn more about whole genome sequencing and their own genomes. In September, the company announced a new service that could deliver a genome in two weeks.

So far sequencing is being used primarily only to diagnose mysterious medical conditions and help treat cancer patients, and by scientists, biotech executives and other people who can afford the out-of-pocket cost.

But the price is plummeting, and many are predicting the $1,000 genome is coming soon. And when that happens sequencing could become much more common.

"I think it's going to be just kind of crazy not to have your genetics known," says Brian Naughton of 23& Me, another genetic testing company. "It would be kind of like not knowing if you are allergic to a drug or not knowing your family history of a disease."

But all it takes to get your genome sequenced is a blood sample, and in weeks you get the results.

This summer Gunderson jumped at a special deal from 23&Me. For $999, he could be one of the first 100 customers to get a big chunk of his genetic code sequenced. It's the part called the exome, which contains all the known genes.

Most of the information would be basically gobbledygook to most people — even most doctors. But Gunderson has learned he didn't inherit an Alzheimer's gene. And he found out a cool reason why — maybe — he made the track team: He has genes found in a lot of Olympic sprinters.

Gunderson still has lots of questions. He wonders if he is carrying any genes that could make him sick.

And he has attention deficit hyperactivity disorder. So he wonders: Could his genes give him any clues about that?

"It might be interesting if there's research that says ... something about the efficacy of Adderall versus another drug that's prescribed for [ADHD]," he says.

He's also curious about other stuff such as why he has trouble sleeping and why he's so particular about food.

While all this might sound appealing, the prospect of lots of people like Gunderson plunging into their genomes makes many people very nervous.

The first big question: Is this cheap, new sequencing even accurate? Mistakes could have horrible implications. Take a breast cancer gene mutation.

"You might be told you have a mutation when you don't. And it's not completely unknown for women who find out they have a mutation in one of these genes to go have a mastectomy so they won't get cancer," says Liz Mansfield of the Food and Drug Administration.

And even when it's right, it could open up a Pandora's box.

"You know, it's a seductive thought to think, well, you know, we might as well know about stuff," said James Evans of the University of North Carolina, Chapel Hill, and the American College of Medical Genetics.

But for most people, sequencing will be just a big waste of time and money, he said.

"We don't just get MRIs on everybody who comes to the doctor's office. Not only would that be ridiculously expensive and uninformative," says Evans, "it could also lead to all kinds of false positives that would be highly problematic for those people."

And sequencing could easily end up stumbling across some terrifying things.

"There are also people walking around out there who carry mutations that create an extraordinarily high probability that they will develop a horrendous, untreatable, unpreventable disease by age 50, 60 years old," he says. "That isn't necessarily information that everybody wants."

It's not just that this might scare people — it could cause really serious, concrete problems in their lives. Getting sequenced could subject people to genetic discrimination for things like life and disability insurance.

There are even more futuristic concerns.

"Individuals who leave samples of their DNA lying around — as we all do every day on straws and napkins and glasses and linen — could have those samples taken and sequenced by third parties," said Mark Rothstein, a bioethicist at the University of Louisville.

It's not totally crazy to think someone, someday could use a person's genetic blueprint to manufacture their DNA and then plant it at a crime scene, for example.

Proponents dismiss most of these fears. They argue that the potential benefits of sequencing, both to individuals and society, far outweigh such theoretical risks.

"For the community of medical care practitioners to decide that it's inappropriate to burden people with this knowledge, it's excessively paternalistic," says Richard Gibbs of the Baylor College of Medicine.

Others argue that people just have a right to have their genome.

"A lot of people just feel like it's their information. They own it," says 23&Me's Naughton. "They want to know."

Gunderson agrees. He's not worried about privacy or discrimination. He even posted all his results so far online and plans to do the same with his full genome.

"A big reason in my mind is like in some tiny way moving science forward by allowing people access to data that they didn't previously have," he said.

As Gunderson waits for the price to drop, geneticists are rushing to figure out how make sure sequencing does more good than harm.

This is the fourth in the "$1,000 Genome" series. Our online survey will close on Oct. 3.

Copyright 2012 National Public Radio. To see more, visit http://www.npr.org/.

Transcript

STEVE INSKEEP, HOST:

The idea of having your DNA decoded as part of routine medical care, is getting closer to becoming an affordable reality. We've been exploring the promise, and perils, of genetic sequencing in our series "The $1,000 Genome." We've already heard from patients who are being helped by this scientific advancement. And today, NPR's Rob Stein takes a look at the consumer marketplace, where sequencing is beginning to really take off.

(SOUNDBITE OF MUSIC)

ROB STEIN, BYLINE: What you're hearing is a video from an iPad app called MyGenome. Now, I'm going to stop the video so I can explain how this app works. Basically, this app allows anyone to zoom in anywhere in their entire genetic code, to see what might be in there.

(SOUNDBITE OF CLICKING)

STEIN: There's this roulette wheel-kind of a thing that lets someone spin through all these genes that doctors know something about. Now, let's see - for example, here's a gene that can tell someone whether they might be at risk for diabetes.

(SOUNDBITE OF CLICKING)

STEIN: Spin through a few more...

(SOUNDBITE OF CLICKING)

STEIN: ...OK. This one - this one's labeled agreeableness. Well, I'm sure I have that one. Anyway, this app came out recently, from a company called Illumina, which is run by Jay Flatley.

JAY FLATLEY: The early adopters that are getting this done now, are those who have this incredible curiosity about their genetic makeup, and about their potential genetic destiny.

STEIN: So far, those are mostly scientists, biotech executives, and other people who can afford to spend between 4- and $10,000. But the price is plummeting, and many are predicting that the $1,000 genome could be here really soon. Brian Naughton says when that happens, sequencing could start to become far more common. Naughton's the top scientist at 23&Me, another genetic-testing company.

BRIAN NAUGHTON: I think it's going to be kind of crazy not to have your genetics known. It would be kind of like - just not knowing if you're allergic to a drug, or not knowing your family history of a disease.

STEIN: Not everyone is as enthusiastic about this - far from it. One big problem is that genes aren't necessarily destiny; not by any means. They rarely tell someone anything for sure. But all it takes to get your genomes sequenced is a blood sample; and in weeks, you get the results. And since it's gotten so fast and easy, and it's getting so cheap, will everyday people soon be lining up?

BEAU GUNDERSON: Yeah, if the price does drop - to a thousand bucks, for example; I might pay that. That's a good, personal price point for me.

STEIN: That's Beau Gunderson. He's 29, and writes code for a Silicon Valley startup. It's people like Gunderson who could make sequencing really take off - not only because it'll help him live a longer, healthier life, but also...

GUNDERSON: Because I'm curious about what makes me tick, essentially.

STEIN: He's already gotten parts of his genome sequenced. And this summer, he jumped at a special deal from 23&Me. For $999, he could be one of the first customers to get a big chunk sequenced - the part with all the genes.

GUNDERSON: Give me one second; I'll grab my laptop.

STEIN: He just got back the results, a few months ago.

GUNDERSON: All right, hold on one second here.

STEIN: Most of the 3 billion chemical letters of the genome...

GUNDERSON: ...loss of a start codon, or loss of a stop codon, so things that change...

STEIN: ...is basically gobbledygook to most people, even most doctors. Still, all this testing has given him some good info. He's relieved, for example, that he didn't inherit an Alzheimer's gene; and he found out a cool reason why, maybe, he made the track team. He has genes found in a lot of Olympic sprinters.

GUNDERSON: I thought it was interesting to see that oh, this thing that I had a kind of talent for, is actually genetic in origin.

STEIN: Gunderson still has lots of questions. He wonders if he's carrying any genes that could make him sick. And he has ADD, so he wonders: Could his genes give him any clues about that?

GUNDERSON: It might be interesting if there's research that said something about the efficacy of Adderall versus some other drug that's prescribed for attention deficit.

STEIN: He also wonders about why he has so much trouble sleeping, and why he's so particular about food.

GUNDERSON: I'm really curious about, like, picky eating and if there's a genetic component to that - because I'm definitely a picky eater. (LAUGHTER) Like, I can't - I just can't do burritos.

(LAUGHTER)

STEIN: Now, this all may sound pretty great. But the prospect of lots of people like Beau, plunging into their genomes, makes many people very nervous. A major concern is whether this cheaper, faster sequencing is even accurate. Liz Mansfield's a top official at the Food and Drug Administration. She says mistakes could have horrible implications. Take a breast cancer gene mutation.

LIZ MANSFIELD: You might be told you have a mutation, when you don't. And it's not completely unknown for women who find out that they have a mutation in one of these genes, to go have a mastectomy so that they won't get cancer.

STEIN: But even when it's right, James Evans says it could turn out to be a big mess. Evans is a geneticist at the University of North Carolina.

JAMES EVANS: It's a seductive thought to think, well, you know, we might as well know about stuff.

STEIN: But for most people, Evans says, sequencing will be just a big waste of time and money.

EVANS: It's like an MRI, right? We don't just get MRIs on everybody who comes to the doctor's office. Not only would that be ridiculously expensive and uninformative, it could also lead to all kinds of false positives that would be highly problematic for those people.

STEIN: And there's a danger that doctors could end up stumbling across some terrifying things.

EVANS: There are also people walking around out there, who carry mutations that create an extraordinarily high probability that they will develop a horrendous, untreatable, unpreventable disease by age - take your pick - 50, 60 years old. That isn't necessarily information that everybody wants.

STEIN: It's not just that this might scare people. It could really cause some serious, concrete problems in their lives. Mark Rothstein is a bioethicist. He argues, getting sequenced could subject people to genetic discrimination for things like life and disability insurance. And he has more futuristic worries.

MARK ROTHSTEIN: Individuals who leave samples of their DNA lying around - as we all do, every day, on straws and napkins and linen - could have those objects taken and sequenced by third parties.

STEIN: It's not totally crazy to think someone could use a person's sequence to manufacture their DNA, and then plant it at a crime scene - for example. Now, proponents dismiss most of these fears. They argue the potential benefits of sequencing, both to individuals and society, far outweigh such theoretical risks. Richard Gibbs is a geneticist at the Baylor College of Medicine.

RICHARD GIBBS: For the community of medical care practitioners to decide that it's inappropriate to burden people with this knowledge, is excessively paternalistic.

STEIN: Others argue that people just have a right to have their genome. Here's Brian Naughton again, from the genetic testing company 23&Me.

NAUGHTON: A lot of people feel like it's their information. They own it; they want to know. And just waiting is not going to help, you know?

STEIN: Beau Gunderson agrees. He's not worried about privacy or discrimination. He posted all his results, so far, online and plans to do the same with his full genome.

GUNDERSON: A big reason in my mind is, like, in some tiny way, moving science forward by allowing people access to data that they didn't previously have.

STEIN: So as Gunderson waits for the price to drop, geneticists are rushing to figure out how to make sequencing do more good than harm. Rob Stein, NPR News. Transcript provided by NPR, Copyright National Public Radio.